Two bugs in the implementation of Largest Contentful Paint (LCP) were fixed in Chrome 83:
For the change that stops measuring LCP at input or scroll in any frame, we see a reduction in LCP at the higher percentiles on Android only (not desktop). Across all sites that use frames, we see the following impact. Sites should expect to see different impacts depending on how they use frames.
We do not see an impact from the background image change in our overall metrics, so we believe the effect on most sites will be minimal. For some sites, the element which is counted as the largest contentful paint could change, and the metric change would depend on the layout of the site.
Chrome 83 is currently scheduled to release on May 19. This page will be updated with an improved estimate of how sites' metrics are impacted within two weeks of launch.